Association of Vitamin D Deficiency with Uterine Atony in Females Delivering at a Tertiary Care Hospital

Abstract

Background: Uterine atony is a leading cause of postpartum hemorrhage and remains difficult to predict using routine obstetric risk factors alone. Vitamin D deficiency may impair calcium-mediated myometrial contractility, but clinical evidence linking vitamin D status with uterine atony is limited. Objective: To determine the association between vitamin D deficiency and uterine atony among females delivering at a tertiary care hospital. Methods: This hospital-based case-control study included 200 postpartum females aged 20-35 years at Sheikh Zayed Medical College/Hospital, Rahim Yar Khan, from 1 January 2020 to 30 June 2020. Cases were 100 females who developed uterine atony within 24 hours of delivery, and controls were 100 females with normal uterine tone. Serum 25-hydroxyvitamin D was measured after delivery, and deficiency was defined as <30 ng/mL. Results: Mean serum vitamin D level was lower in cases than controls (22.35 ± 9.02 vs 28.48 ± 10.53 ng/mL). Vitamin D deficiency was present in 84.0% of cases and 57.0% of controls, corresponding to a crude odds ratio of 3.96 (95% CI 2.04 to 7.70; p<0.001). Conclusion: Vitamin D deficiency was significantly associated with uterine atony, although prospective studies are needed to confirm temporality and causality.